Marijn
Don't be. You're doing valuable work and there's no need to let people stress you out for free. I set an expectation that commercial users pay me on my project's web sites now.
I might help non-paying users, because they found interesting bugs, or there's money left over from paying users, or because I'm feeling nice, but I don't have to—my time is valuable, and I don't owe random consumers of my work anything.
Strypey
@marijn totally agree with what you're saying here. One thing that came up in discussions on a #NZOSS mailing list was that many business people want to pay a fair amount to support the long-term viability of free code projects, but business accounting makes it difficult for them. If they can itemize the spending as a business expense, rather than a charitable donation, or worse just giving money away, that makes it much easier.
Strypey
@marijn I recommend every project that maintains #FreeCode software for end users puts a pricing page on their website, laying out the cost of commercial license(s), and what support paying users can expect to get. Obviously you'll need to do proper invoicing etc. But you might be surprised how many people will pay to get their itches scratched promptly, if the price is reasonable, even if the software is free-as-in-freedom. I especially encourage this for anyone running libre network services.
Strypey
@marijn every wondered how all the third-party apps Windows users download (eg Spybot) make enough money to keep going, for decades in some cases? Simple. Tell users they're supposed to buy a license for businesses use. You don't need all of them to actually do it (how would anyone know?), just enough of them to keep the lights on.
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